Blackpack

Violent shaking in my 48 Super

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Question. What are the three or four set screws for on the pinion gear cover right behind the torque tube? Do those ever need adjusting?

Locks the front pinion bearing against shims in the case...all that should be in your service manual ;) .  Do you have a service manual? :unsure: 

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 Reading through this, I don't know what to say. I was wondering about a bent/damaged axle shaft, but that would get worse the faster you go, likewise if there was some issue with the gearing in the axle, it might be OK at slow speeds but would get worse as speed increases. Does anything like that happen?

If it drives smooth at say 30-40 MPH, then I would still think that the issue resides somewhere in the clutch/tranny/mounting.

What happens if, when driving, you quickly let up on the gas pedal, then back on it, hard? Any bad noises/clunks?

Also, could something like a small webcam be mounted in 2 or 3 places underneath the car to see if something is moving more in one place than another? You could use one camera and move it around from place to place.

Keith

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Keith,

I think we have eliminated the clutch, tranny, and motor mounts. There is no shaking of the car or movement of the engine while brake is on and pushing on the gas. No vibration in pedal either. Only under load and when starting in first or reverse from a dead stop. No shaking once clutch pedal is all the way up and car is rolling. Shifting is fine. Starting out in second isn't much better

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Keith,

I think we have eliminated the clutch, tranny, and motor mounts. There is no shaking of the car or movement of the engine while brake is on and pushing on the gas. No vibration in pedal either. Only under load and when starting in first or reverse from a dead stop. No shaking once clutch pedal is all the way up and car is rolling. Shifting is fine. Starting out in second isn't much better

 

If you have eliminated the clutch and motor mounts then you don't have a problem. Have you measured the crankshaft end play/thrust?

Have you put it against a tree and tried to smoothly engage clutch? Bernie wasn't just having fun with you, it is a good way to check it.Be sure to have someone watch the engine to see if it flops like a fish.

Edited by TexasJohn55 (see edit history)

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Keith,

I think we have eliminated the clutch, tranny, and motor mounts. There is no shaking of the car or movement of the engine while brake is on and pushing on the gas. No vibration in pedal either. Only under load and when starting in first or reverse from a dead stop. No shaking once clutch pedal is all the way up and car is rolling. Shifting is fine. Starting out in second isn't much better

 

I still think the issue is in the clutch area. Mine shakes a bit in first and second.  The clutch pressure plate is new?     

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John,

Yes, I have a lot of respect for Bernie's comments and help. In fact, I'm about ready to offer him a plane ticket to come out and look at this thing. We did power brake it and the clutch did not vibrate and the car did not shake. The motor was in view and stayed in place. The mechanic placed boards between the rear axle and underside of the body and strapped it down tight. This was done to eliminate the shocks. If was a tiny bit better, but still shook badly. Pinion gear looks good too. Now the concentration is back on the u joint. The person who rebuilt the tranny said he checked the u joint and it checked out, but I'm not sure if it was actually removed. I think I'm going to buy a go pro camera and mount it under the car and have the mechanic drive it. This is really frustrating

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Chris, I have replaced just about everything from the back of the motor to the rear axle excluding the transmission case

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Thanks for seeing through the western New York colloquialisms and catching that these are things I would really do on my own car. I'd make it shake. If someone standing by didn't see what was wrong I'd shake it until I broke something.

 

Just a random thought; that car should have a diaphragm pressure plate. Could they have slipped a 12 spring B&B in there when the clutch was replaced?

 

I am contemplating a ride out to Mooresville, Indyanna. Maybe that's not far?

Bernie

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Maybe it is a bad case of "cowl shake", after all it is a convertible.       Have     you    checked    the      crank     thrust     ???

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Bernie,

I will check with the mechanic on the preassu re plate. I am lucky enough to have Walter Habeeb nearby that is very active in the local Buick club chapter and owners several Buicks. He takes his cars to the same mechanic and has made a few visits to the shop to help out. Mores ills is only about 15-20 minutes down the road from Franklin, IN where I live

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My little convertible doesn't even have a frame and I don't get cowl shake. Maybe it knows I'd use the "bigger hammer" in the background if it misbehaved.

 

There is a '40 Lincoln Continental parts car in Mooresville I could use, certainly not need, but could use. I seem to attact temptation.

Bernie

 

post-89785-0-42884300-1433937646_thumb.j

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Bernie,

I will check with the mechanic on the preassu re plate. I am lucky enough to have Walter Habeeb nearby that is very active in the local Buick club chapter and owners several Buicks. He takes his cars to the same mechanic and has made a few visits to the shop to help out. Mores ills is only about 15-20 minutes down the road from Franklin, IN where I live

 

 

This is the pressure plate that came out of my 54:

 

IMAG0796_zps8d5c6117.jpg

 

 

This is what went in:

 

IMAG0797_zps4a6fb1dc.jpg

 

This the assembly installed:

 

IMAG0802_zps86648e65.jpg

 

Does your torque ball assembly have the brass bushing ring installed.:

 

IMAG0786_zpsbd708828.jpg

Edited by avgwarhawk (see edit history)

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Okay, so I guess the pressure plate was not changed with the rebuilt clutch disk, so I have ordered a new pressure plate. I called Bobs Automobilia and they assure me that a new style pressure plate will work with an original style clutch disk. They said that a new style clutch disk will NOT work with an original style pressure plate. This HAS to be the problem. There is nothing left to replace!

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Okay, so I guess the pressure plate was not changed with the rebuilt clutch disk, so I have ordered a new pressure plate. I called Bobs Automobilia and they assure me that a new style pressure plate will work with an original style clutch disk. They said that a new style clutch disk will NOT work with an original style pressure plate. This HAS to be the problem. There is nothing left to replace!

 

Confirmed with the mechanic?  Seems odd for just getting the clutch and not the pressure plate in one box. Although it can come that way. 

 

Yes, the clutch plate I had removed was exactly the same as the new one I installed. Works great. 

 

The new two piece clutch was as pictured above.  The pressure plate and clutch are used on a 80's Jeep if I remember correctly. If the old pressure plate is still installed I suspect it is weak and allow the chatter/vibrations.   

Edited by avgwarhawk (see edit history)

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Just confirm with the mechanic the old pressure plate was reinstalled. If the pressure plate is new then it may not be the problem

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My mechanic did, indeed reinstall the old pressure plate because the dealer I bought the car from claimed it was new. Unfortunately, we have learned that the dealer has not been very honest about anything regarding this car and so that left enough doubt in our minds. Plus he said he didn't mind putting it on if I would buy the part. He has become a real pro at tearing this car apart and putting it back together.

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Well I think that could be the culprit. Should be changed anyway.

Speaking of taking cars apart and reassembly numerous times my wife's Pontiac Lemans(the ugly one from the 80's) I had changed the timing belt so many times I could do it in 30 minutes. Same with the ever present cv joint replacement. The last straw was the headlight switch melting in the dashboard.

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It's not always obvious to someone new, but if you climb into the back seat and look in the top right corner there is a zipper. And the whole thing just comes apart.

Bernie

 

 

post-89785-0-84554200-1434025934_thumb.j

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Okay, so I guess the pressure plate was not changed with the rebuilt clutch disk, so I have ordered a new pressure plate. I called Bobs Automobilia and they assure me that a new style pressure plate will work with an original style clutch disk. They said that a new style clutch disk will NOT work with an original style pressure plate. This HAS to be the problem. There is nothing left to replace!

 

To be sure you have the old style pressure plate?  The reason I ask is my 54 had the clutch replaced in 04(previous owner).  It had the old style pressure plate pictured above.  The clutch disc that came out looked exactly like the new clutch disc going in.   Bob's Auto said the old style pressure plate does not work well with the new style clutch disc.  If that is the case than I too experienced the same as you.  Clutch chatter/vibration in 1st. Some in 2nd. Chatter in reverse.  Recall my post in your original thread were I stated there was gear oil leaking like Niagara Falls?  It may not have been just the gear oil creating the chatter/vibration but the mis-matched old style pressure plate and new style clutch.   Whatever the case, the new improved pressure plate and disc took away the chatter/vibrations.  

 

Food for thought.     

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Good morning everyone! I received encouraging news this morning. I stopped by the Mechanic and he had my old pressure plate out of the car in preparation for the arrival of the new pressure plate today. The pressure plate that came out was a diaphragm type that looks new. However, when measuring from side to side, there is about a 1/4" difference in space. Looks like it is warped badly. The new pressure plate is a 12 spring type and I have been told that it will work with the original style clutch disk. Keep your fingers crossed, but I may finally be getting this car back today!

Edited by Blackpack (see edit history)

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 That sure sounds like it might be the issue. I'm looking forward to hearing the outcome! They're really nice cars to drive, so I hope you will get to enjoy it soon!

 Keith

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Stopped this morning to see if the mechanic received the new Pressure Plate on Friday and all the receptionist would say is that she was not supposed to talk to me about it and that I needed to go back to the garage area and talk to the mechanic/owner. I didn't have a good feeling. He said that the delivery driver dropped the new part off at closing time on Friday and he stayed Friday night to put the tranny and rear end back in. Took it off the lift, put it in gear and IT STILL SHAKES!!!! The old pressure plate was definitely warped and I can see where it is was contacting the flywheel unevenly. I just don't know what else to do. The mechanic has already put a bunch of overtime into fixing this thing, working weekends, holidays, and evenings and he has run out of ideas. He is now calling around to some old timers to get help. He doesn't want to give up, but I know he is losing money hand over fist on this car (unless I get hit with a huge bill) and I know he wants his lift back. It's now been in his shop 97 days. I feel like I ought to just take the car back, but I don't know who else to turn to. I just pray to God that the end of the crank isn't bent. You guys have been great with your advice and we have tried everything that has been discussed on this thread except for removing the torque tube and looking inside. I think that is going to be my mechanic's last attempt at fixing this. I'm afraid I just bought a very expensive chunk of metal. Seller of car and inspection company will not return emails so I guess I'm on my own

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I'm sorry sir. At a total loss after all that has been done.  What looked so promising as the issue has proved to be incorrect.

 

If anyone can answer, does the inline 8 have a balance on the crankshaft?     

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